4)2D3D-MatchNet [1]} is the only prior work for cross-modal image-to-point cloud registration to our best knowledge. However, the rotation between camera and Lidar is almost zero in their experiment setting. This is because the images and point clouds are taken from temporally consecutive timestamps without additional augmentation. In contrast, the point clouds in our experiments are always randomly rotated. This means 2D3D-MatchNet is solving a much easier problem, but their results are worse than ours.
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